A Cubic Mile of Oil

Monday, November 7, 2016

The number times the subject of
energy was brought up by a moderator in this year’s three Presidential debates
is precisely zero. The only time the issue came up was during the town-hall style
debate in St. Louis citizen when Ken Bone asked the candidates, “What
steps will your energy policy take to meet our energy needs while at the same
time remaining environmentally friendly and minimizing job layoffs?” In his brief
response, Trump berated the Obama administration and the EPA for “killing” our
energy industry and letting foreign companies come in. He was forgetting
that more than the EPA it is the abundance of cheap gas that is killing coal
production. If oil and gas is production is increased, so will the economic
pressure to close coal mines. And, yes we do need regulations; thanks to the
Clean Air Act emission of toxic particulates from coal power plants have been
markedly reduced, and as a result we are all breathing easier.

In her statement,
which was cut short by the moderator, Clinton only emphasized the need to revitalize
the coal country as coal prices are down globally and the government can’t walk
away from miners and other workers of the region. We missed a great
opportunity to hear our candidates lay out their policies on this very
important topic.

Hillary Clinton wants to invest heavily in transforming the US
energy supply and touts the large number of green jobs that will create.While consideration of jobs is understandable,
I think the emphasis on the number of jobs in energy industries is misplaced.
The role of the energy industry is not to employ many workers within itself,
but to produce a commodity at an affordable price to enable other industries
and businesses to flourish and in so doing provide employment for many. We
don’t necessarily want many people employed in the production of energy—a commodity; rather we want more people
employed in the consumption of
energy. Wages for every employee engaged in production add to the cost of
producing the commodity, making it more expensive for other businesses and
industries to use it and employ more workers.

It is true that green energy employs many more people, but to get
more quantitative—which is my wont—I browsed through the databases published by
the Bureau of Labor Statistics to cull some relevant data. For the amount of
energy produced by each sector, I used the data from the 2016 BP Review of Global Energy. Whereas the BLS continues to track
the numbers for the Oil and Gas, Coal, Nuclear, Hydro, and many other
industries, it stopped tracking Green Energy jobs in 2013—a casualty of the
sequestration that went into effect when the Congress could not agree on a balanced
budget. Besides, its definition of “green jobs” was very broad. Fortunately,
the International Renewable Energy Agency does track the global
employment in wind, solar, and other renewable technologies.

The following table lists the number of workers employed in
the different energy sector and the amount of energy produced by them. For the
first four entries the numbers refer to the US only, but for Wind and Solar
they refer to global employment and global energy production. The relevant
point for comparison is the per capita productivity. Whereas each worker in the
Nuclear power produces over 100 GWh/year, the productivity of workers in the wind
power sector generate less than 1 GWh/yr, and in the solar less than a tenth of
that. At this rate, the solar power sector would need to employ about 43 million
workers, or roughly a third of the US workforce, to generate the 4,000 TWh of
electricity that the US currently produces and consumes!

Table
1. Per capita energy productivity is the highest for nuclear power.

Monday, June 6, 2016

I haven’t been paying much attention to the statements made
by the presumptive Republican nominee, Mr. Donald J. Trump. His bombastic and
inflammatory comments early in the campaign had turned me off. On May 26 he
gave speech on energy policy at the Williston Basin Petroleum Conference, in
Bismarck, North Dakota. A friend sent me a news clip of his speech wondering if
his statement about the relative oil reserves of the US and OPEC were correct.
Energy happens to be a subject that I am quite familiar with: having worked in
the area for thirty years and written a book
and blogging
on the subject. My immediate response upon hearing him was that he was totally
wrong. US oil reserves are only a fifth of those of Saudi Arabia, and even with
the recent gush of shale oil, the US reserves remain a tiny fraction.

What puzzled me was why a candidate for the US Presidency would
make such an obvious mistake. And so I listened to his statement again; this
time very carefully to see if I had missed something—and indeed I had. Here is
a link to his full speech.

In a single sentence Trump says that the US has 1.5 times
oil than the combined reserves of OPEC. One would think that when he says
"US has 1.5 times oil" he is also referring to the oil reserves of
the US, otherwise the comparison would not make much sense. But he did not say
that US reserves of oil are 1.5 times
those of OPEC. He only said that US “has 1.5 times oil…” Such a comparison
would be as meaningless as me saying I have more money than Trump has cash in
his pockets—a statement while most likely true is totally disingenuous and insincere!

Here are some numbers in cmo units—cmo stands for a cubic
mile of oil and is equal to 26.2 billion bbl (barrels) or 3,784 million metric
tons of oil equivalent (MTOE). US oil reserves are less than 2.0 cmo; Saudi
Arabian reserves are over 10 cmo. The reserves of all OPEC countries add up to
43 cmo. Russian reserves are about 4 cmo. If by “has” Trump is referring to all
US resources, including oil shale (not just shale oil, which can be produced by
fracking), then yes he may be correct. US has an estimated 70 cmo of oil shale,
but for whose recovery we do not have an economic technology. Remember, oil
shale is that vast resource that has oil precursors embedded in shale, but the
geology has not yet done the job of producing the oil. We have to dig up the
rock and heat it to produce the oil or heat it underground to liberate the oil.
For a fairer comparison of respective resources we should look at the resource
base of OPEC too, which is estimated at about 40 cmo on top of the 43 cmo of
reserves.

Trump also makes the audacious claim that the US has more
natural gas than Russia, Iran, Qatar, and Saudi Arabia. The natural gas
reserves of the US are 2.2 cmo, while those of Russia are 4.0. The combined
reserves of Russia, Iran, Qatar, and Saudi Arabia are 23 cmo. Hard as much as I
try, I cannot rationalize Trump's statements about natural gas.

A basic premise of Trump’s speech was that the regulations
had been curtailing production in the US energy resources. He wants to declare
US energy dominance a strategic, economic, and foreign policy goal. He would
achieve that goal by getting rid of those onerous restrictions by the EPA and
other agencies. He will cancel the Paris Climate Agreement (COP21) and stop all
payments of U.S. tax dollars to U.N global warming programs.

His main assumption is that once the regulations are gone, the
oil and gas industry could ramp up production and bring wealth to America. This
line of reasoning takes no account of the fact that the global market is
already oversupplied. Increasing US production will only further depress the
prices and make much of the US production uneconomic. When oil prices fell from
$100/bbl in 2014 to below $30/bbl in 2015, investments in new drilling ceased,
rig counts plunged from 1900 to 400, and many boom towns in North Dakota,
Montana, and Texas became emaciated skeletons of their roaring days. This
decline was not a self-inflicted wound; it did not occur as a result of
EPA-imposed regulations. In order for the US oil to garner a greater share of
the global market, it would have to undersell
the low priced competition from Saudi Arabia—and there goes the economic
incentive for any oil producer in a free economy.

Trump blames regulations like the Clean Power Production as
the chief reason coal production and use in the US has dropped sharply—from
producing 50% of US electricity to producing only 33%. The Clean Air Act and
its amendments dating from the 1970s and 1990s increased the cost of
electricity from coal, but they did not remove the dominance of coal in power
production. The main reason for the decline has been the availability of cheap
natural gas. Cleaner and cheaper natural gas has made coal burning power plants
relatively uneconomical. Under Trump’s plan, restrictions on fracking for oil
and gas would be lifted and flood the market would be further flooded with
cheap gas, which would only hasten the demise of coal. Those coal mining jobs
that he talks about cannot be restored as long as there is an abundance of
natural gas, unless he artificially raises the price of natural gas. He cannot
have both gas and coal industries flourish simultaneously—at least not in a free
market democracy.

According to Trump, “President Obama entered the United
States into the Paris Climate Accords – unilaterally, and without the
permission of Congress. This agreement gives foreign bureaucrats control over
how much energy we use right here in America.” To begin with COP21 is an
Agreement, not a treaty that would require congressional approval.Under COP21 foreign bureaucrats do not
control how much or how we use energy in America. In fact, the Agreement relies
solely on “intended nationally determined contributions (INDC),” which are put
forth by the signatory nations themselves.The problem with COP21 is that the current set of INDCs do not go far
enough to meet the reductions required to limit the Earth’s warming to 2°C
above the pre-industrialization level.But then again, Trump does not believe in climate change results from
greenhouse gases.

What these considerations show is that Trump lacks the basic
understanding of the facts of the global energy market—who has what and how
much. He has no appreciation of the interrelatedness of the energy markets.
Given the centrality of energy in matters of national security, foreign
relations, and trade, I am afraid that should Trump become our next president,
we better fasten our seat belts—it’s going to be a very bumpy ride.

Friday, March 11, 2016

This is a long overdue
post!The BP Statistical Report came out
in April, the Pope’s Encyclical was published in June, oil prices have stayed
below $50 a barrel for over a year, the Obama administration issued its Clean
Power Plan in August, Climate Talks in Paris were held in December.Lots of items to cover, so let’s get down to
it.

Overall Energy Use

First, a quick review of
the global energy scene in 2014 as reflected in the BP Statistical Review of
2015.Since 2006, the year for which the
data were used in the writing of A Cubic
Mile of Oil, energy use has increased from 3.19 cmo to 3.74 cmo. Most of
0.55-cmo increase in energy consumption since 2006 has come from increased use
of coal (0.23 cmo), natural gas (0.14 cmo), and oil (0.10 cmo), and not
surprisingly, the global emission of CO2 from energy use increased
from 31.2 GtCO2 in 2006 to 36 GtCO2 in 2014. The updated
pie charts of energy sources are in Figure 1.

Figure
1. Distribution of sources of global primary energy in 2006 and 2014.

Energy consumption in the last
8 years has increased by 17.4%. The period includes the financial crisis of
2008 and a marked decline in energy consumption and economic output for two
years. Yet, the net increase in energy consumption corresponds to a compounded
average growth rate (CAGR) of almost 2%. I should note that the increase in
energy demand in 2014 was less than 1% compared to the 2-3% increases seen in
recent years.The low energy demand
reflects a softening in the global market. Annual GDP growth in China is down
below 7% and there is considerable economic uncertainty in several European
countries such as Greece, Spain, Italy, and Russia.

Nuclear Power

There was a noticeable
reduction in the production of nuclear power; from 2806 TWh (0.17 cmo) in 2006
to 2537 TWh (0.15 cmo). The share of nuclear nuclear power to primary energy consumption
dropped from 5.4% to 4.0% during this period. Japan shut down all its nuclear
power plants following the massive earthquake and tsunami in 2011, which caused
a major accident at Fukushima. Japan has now begun the slow process restarting
those plants. The plan is to resume generating power from all the plants by
2020 but there remains much public opposition to restarting nuclear power plants.

Following the general
elections in 1998 Germany’s coalition government, which for the first time included
the Green Party, adopted a plan to phase out nuclear power. The new Social
Democratic Party government led by Angela Merkel reversed that policy in 2009,
but reinstated it following the Fukushima disaster. It closed down nine out of the
17 power plants, as a result, instead of providing 25% of domestic electricity,
nuclear power provided only 16%. Between Germany and Japan, almost 360 TWh of nuclear
power production was lost. Some of the lost nuclear production was made up by
increases in China (72 TWh) and India (17 TWh).

Replacing the loss of 300
TWh of nuclear power by coal would increase CO2 emissions by 0.3 Gt
CO2, or about 6% of the increase in emissions since 2006. The steady
increase in CO2 emissions does not augur well for climate change.
The IPCC reports have been steadily increasing the certainty with which
anthropogenic emissions of greenhouse gases (GHG) are expected to cause
catastrophic damage. Shutting down nuclear plants at a time when there is an
urgency to transition to CO2-free energy is counterproductive.

Low Oil Prices

Starting in mid 2014,
crude oil price began a precipitous decline from over $100/bbl to the current
price of about $35/bbl. There are a number of factors for this decline. Commentators
in the US tend to attribute this decline to the rise in the US production of
tight oil (aka, shale oil). Since 2006 the US oil production has steadily increased
by about 3 million bbl/day. It may seem a small fraction of the global
consumption which is around 90 million bbl/day, but given the tightness in the
market between the supply and demand, a swing of 3 million bbl/day is
significant.However, the story of low
oil prices a bit more complicated and involves events and policy changes
elsewhere in the world as well. Increase in US production took place at a time
when global demand was high and when events in the Middle East had constrained
the supply. The excess oil in the US more or less offset the loss of oil from
Iraq and Libya in the world market. When Iraq oil started to flow and the
global demand was softening a global glut was imminent, but that was prevented
by the sanctions against Iran. Now with prospects of the nuclear deal and the
lifting of the sanctions, 2.5 million bbl/day from Iran would once again flow
into the global market and that fact combined with low demand has depressed oil
futures. For over 40 years now, the US has had a policy of not exporting crude
oil. With the recent availability of excess domestic crude, the US refiners increased
their capacity to produce refined fuels—something that was also aided by the
increased supply of fracked natural gas. The US recent lifting of the US ban on
exporting crude oil only exacerbates the situation and further depresses oil
futures.

Saudi Arabia has
traditionally played the role of the swing producer and. as recently as 2013,
dropped its production by a million bbl/day to stabilize oil prices. In June
2014 Saudi Arabia reversed its policy and decided in favor of retaining market
share by increasing oil production back up to over 10 million bbl/day. This
oversupply caused the oil prices to tumble and while it has been largely a boon
to oil consumers, the price drop is causing economic hardship in many oil
producing countries, including Russia, Brazil, Venezuela, Iraq, and also Saudi
Arabia itself.

Saudi Arabia’s has
sufficient cash reserves to support running the current level of deficit for
about five years. It is counting on the fact that many of its competitors will
not be able to sustain their deficits that long, and will be driven out of
business. Under the current circumstances it makes little sense to drill for
new oil, particularly in hard-to-produce resources like tight formations, deep
water, or under the Arctic Ocean. Companies will produce oil only from wells
whose up-front costs have already been paid and for which the cost of continued
production can be recovered at the prevailing price of oil. Wells that are no longer economical will be
shut down.

Saudi Arabia’s strategy
has already had an impact in the US where rigs used for fracking oil is down
from 1900 in January 2015 to 650 in December. The total oil production dropped
by 400,000 bbl/day. That the drop in rig count is far more precipitous than the
drop in production reflects the fact that there is little appetite for digging
new wells, and it is wells with poor productivity that get shut down first. If
and when the oil price increases oil from fracked formations can resume in a
short time. This quick start-up and shut-down of production allows fracking
companies to act as the new swing producers. However, if the low prices
continue for several years and investments in new production and distribution
facilities are not made, any future rise in oil prices will likely be very
steep.

Rise of Renewables

The past eight years have
witnessed a marked increase in the production of electricity from wind, solar
and geothermal energy sources, from 138 TWh in 2006 to 992 TWh in 2014.The installed capacity of wind increased
five-fold from 74 GW to 373 GW, and for solar it soared 27-fold from 6.7 to 180
GW. The last eight years have seen a substantial drop in the cost of electricity
from these technologies. In 2006, PV panels used to sell for about $3/watt,
their price has dropped to about $0.75/watt.The levelized cost of electricity from solar in 2006 was around 36¢/kWh;
in 2015 it is below 10¢/kWh.Many Power
Purchase Agreements (PPAs) from solar facilities in 2015 have electricity priced
at less than 5¢/kWh. Most notably perhaps are the two agreements signed by the
utility NV Energy, owned by Warren Buffet’s Berkshire Hathaway: one with SunEdison
for power from a solar plant in Colorado for 4.6¢/kWh; and the other with First
Solar for power from their plant in Nevada for 3.87¢/kWh. Wind power prices
have also come down over these years. In
2006, wind energy costs were about 15¢/kWh; in 2015 PPAs signed for wind power
in the interior states in the US having a purchase price of about 2¢/kWh. These
low prices do come with subsidies in the form of a 30% investment tax credit
for the solar power and a 2.3¢/kWh of production tax credit for wind
power.

Since 2000 wind and
solar power have enjoyed an exponential growth in production. The growth has
been driven by market forces—falling prices—as well as government policies like
Energiewende in Germany and Renewable Portfolio Standards in many
states across the US. Advocates of of these energy sources project this growth
to continue at this level or even at an accelerated pace such that electricity
production from these sources will soon provide the majority of global
electricity, which in 2014 was 24,000 TWh. The graph below (Figure 2) shows the
amount of electricity produced by wind and solar plants on a logarithmic scale.
While it is true that for a period solar installations were doubling every two
years and wind every four, the doubling rate has slowed down. The slow down
since 2011 relative to the growth during the preceding five years is a sobering
reminder that once the installation base gets large enough resource
constraints—such as material supplies, labor and capital—slow down the process.
Rosy forecasts by proponents notwithstanding, unless drastic policy measures
are taken, it does not look like wind and solar will generate even 10,000
TWh/yr by 2025, by which time total electricity demand could well exceed 36,000
TWh.

Figure 2.Growth of wind and solar power generation has
been remarkable, but current rate is not fast enough to allow wind and solar to
be the dominant electricity producers by 2030.

Battery Storage

Storage of electrical
energy is an important factor for increasing the penetration of intermittent
sources like wind and solar.The only
significant electrical storage capacity in the grid currently is in the form of
pumped hydro. Although there are a number of battery systems, such as flow
cells and liquid metal cells, in early stages of development, they currently do
not provide any grid-level storage.

Noteworthy advances in Li-ion
batteries have also been made in these intervening years. In 2006 Li-ion
batteries cost about $1000/kWh, and that was a serious impediment to their broad
application electric cars. Cost of Li-ion batteries has now dropped to about
$300/kWh. The 24-kWh battery pack in Nissan Leaf cars, which cost an estimated
$18,000 in 2010 can now be replaced for $5,500 plus the used battery.If we include the $1,000 for value for the
used battery, the cost of the new battery pack would be $6,500 or
$270/kWh.Life of the battery packs has
also increased through better management of heat and charging/discharging
currents.A lifetime of over 1000 deep-discharge
cycles is now quite typical. For residential applications Tesla announced its
PowerWall units in April 2015. Each $3,500 unit can store 7 kWh—there is also a
10 kWh unit available for $3,500. The price is still steep for use as a simple
backup power system during power outage; the main value of these units is for
homes with PV systems as they extend the use of solar power during nighttime
and largely eliminate the need for grid power.

CO2 Emissions

There has been increasing
pressure on the world’s largest emitter, China, and the largest per capita
emitter, the US, to curb emissions. US and China emissions of CO2 in
2006 were 6.4 and 6.9 Gt respectively. In 2014, the US emissions were down to
6.0 Gt, but China’s emissions had risen to 9.8 Gt. On a per capita basis, US
emissions still far exceed those of China—18 metric tons per capita in the US
versus 8.2 metric tons in China. In Nov. 2014 presidents Obama and Xi Jinping
signed an accord under which the US would reduce its GHG emissions to 28% below
2005 level by 2025 and China would peak its emissions by 2030 after which it
would reduce them. President Obama followed up that pledge by issuing the Clean
Power Plan (CPP) in Aug. 2015 under which there would be a federal standard for
reducing CO2 emissions from power generation by 32% over 2005 levels
by 2030, but it would be up to individual states to determine the mix of
technologies to achieve those goals.

It is not clear how successful CPP will be in
cutting down GHG emissions. Market forces have already led to a substantial
reduction of emissions in the US by the switch from coal to natural gas, and
perhaps more could be achieved with further decline in the cost of wind and
solar power. Politically, the CPP has not garnered much support.Many state governors have already announced
their opposition to The CPP. Nevertheless, the joint agreement with China and
the CPP have helped pave the way for the COP21 Climate Talks in December.

The Papal Encyclical issued
in July also drew attention to the growing threat of climate change and its
disproportionate impact on the impoverished.Pope Francis noted, that “… our industrial system, at the end of its
cycle of production and consumption, has not developed the capacity to absorb
and reuse waste and by-products,” and called for “changes of lifestyle, production and con­sumption, in
order to combat this warming or at least the human causes which produce or
aggra­vate it.” His statements about combating climate change received much
attention, but there was another deeper message in his statement, the one about
consumerism and social injustice it engenders when “(w)e fail to see that some
are mired in des­perate and degrading poverty, with no way out, while others
have not the faintest idea of what to do with their possessions, vainly showing
off their supposed superiority and leaving behind them so much waste which, if
it were the case everywhere, would destroy the planet.” The pope recognized the
need for vastly expanding renewable energy sources, but also noted that, “(f)or
poor countries, the priorities must be to eliminate extreme poverty and to
promote the social development of their people.”

Around the same time as
the Pope’s Encyclical, the World Bank also issued Sustainable Development Goals for the world which lists goals and
targets in 17 areas: eradicating poverty, providing adequate food and clean
water, reducing gender inequality, taking urgent action to combat climate
change, and ensuring access to affordable reliable energy is listed among the
goals. Achieving most of these goals requires increasing global energy supply.
Speaking about the enormous progress the world already made Dr. Jim Yong Kim,
president of World Bank noted that over a billion people have been lifted out
of poverty in the last 25 years, and he could foresee lifting another billion
in not too distant future.

The progress Dr. Kim noted
was made on the backs of coal and oil. Can we afford to do the same to help the
next billion? The SDG of removing poverty runs up against the need to curb CO2
emissions. Unfortunately, the one CO2-free energy source that is
capable to generating the required scale of power, nuclear, is something that
the World Bank does not support developing. In view of its policy of not
funding nuclear power I have to wonder how serious is the World Bank about the
SDGs.

In early December 2015
with much fanfare about 200 nations signed the COP21 Agreement to curb global
GHG emissions. It was an unprecedented achievement given the previous failed
attempts.All nations acknowledged the
peril the world faces from climate change being engendered by continued
emission of GHG, principally from the use of fossil fuels. The countries
pledged to cut down their GHG emissions either in absolute numbers or relative
to an expected business-as-usual (BAU) scenario. The individual countries
determine the GHG reductions they pledge to make. However, there is no
mechanism of punitive action to force the countries to stick to the pledged
contributions except a public shame. The intended nationally determined
contributions (INDCs) are reported to the UN and the emissions of each country
are measured and reported in an agreed-upon standard way, and both these are in
the public domain. The lack of enforcement is a recognition of political
realities; any Agreement that had forced compliance would not have had the
support of many countries.

COP21 Agreement sets a
goal of limiting the rise in global to temperature to 2°C above the
pre-industrialization level, with a stretch goal of limiting the rise to 1.5°C.
Even achieving the 2°C target is a daunting challenge, and requires a major
upheaval of the global energy system. It would require achieving a net zero
emissions by 2050, and limiting total emissions to about 350 Gt CO2. The world currently consumes about 3.6 cubic miles of oil equivalent (cmo) of
primary energy and emits over 36 Gt CO2 from energy use.Under BAU the annual energy consumption is
expected to rise to more than 6 cmo by 2050. Burning of each cubic mile of oil
releases 12 Gt CO2, about 17 Gt if it is from coal and about 8 Gt CO2
if natural gas is the source of the energy. Even under an all-renewable, all-electric
scenario, which could conceivably avoid two-thirds of the primary energy, an energy
consumption of 6 cmo/yr would lead to a requirement of generating of 82,000 TWh
of electricity relative to 24,000 TWh in 2014; in other words, more than
tripling the current global electricity production.

I found it appalling when
it was brought to my attention (thanks to Morgan Bazilian) that the word energy appears only three times in the 31-page Agreement. The word
appears twice on page two where the Conference of Parties “acknowledges the
need to promote universal access to sustainable energy in developing
countries, in particular in Africa, through the enhanced deployment of
renewable energy.” The third time the word is used is on page 31 as part
of the the name of UN’s IAEA:International Atomic Energy Agency. No wonder then that there is
such huge chasm between the target reductions in CO2 and the pledged
INDCs.

I paint a rather gloomy
picture, but I would like to end on a more hopeful note. Perhaps the most
important outcome of COP21 was the formation of the Mission Innovation fund by
many prominent philanthropists like Bill Gates, Richard Branson, Jeff Bezos,
Mark Zuckerberg, and others to help innovative solutions cross the “valley of
death” and transition to commercialization. They have been joined by 20
governments to double the collective annual budget of energy research from $10
B to $20 B. It may be too little too late, but I can only hope some of the
Mission Innovation funds will provide the necessary support to bring the
nascent nuclear power technologies that are inherently safe and scalable to
market.

Friday, June 12, 2015

I have often been asked questions like how
many cubic miles of CO2 do we produce when we burn a cubic mile of
oil, and how many ppms does that represent. In this post, I will make some
simplifying, yet reasonable, assumptions to provide answers to these and other
questions.

In round numbers, one cubic mile of oil
weighs 3.8 billion tons and contains roughly 3.2 billion tons of carbon. Burning
this quantity of oil produces 153 quadrillion Btu of energy, which we have
defined as 1 cmo. This combustion produces about 12 billion tons or 2.7*1014
moles of CO2. As a gas, the volume of CO2 is depends on
the pressure and other variables. But let’s say we condense it into a liquid. Liquid
CO2 has a density of close to that of water. As a liquid the amount
of CO2 from burning a cubic mile of oil will occupy 3 cubic miles. If
we burn coal to get an equivalent amount of energy, we produce 17 billion tons of
CO2, which as a liquid would take up 4.3 cubic miles. Burning
a cmo worth of natural gas will generate 7.5 billion tons of CO2—about
1.9 cubic miles of liquid CO2.

To determine by how much the
concentration of CO2 in the atmosphere changes when we burn a cmo of
oil, we need an estimate of the number of moles of gas in the earth’s
atmosphere. Here’s a guesstimate. The radius of the earth is 4000 miles, and so
its surface area, 4*pi*r2, is approx. 200 million square miles, and if
we assume that the atmosphere extends to only 5 miles, the volume of atmosphere
is 1 billion cubic miles. If we assume that the pressure in this 1
billion cubic miles is 1 atmosphere and 27°C (it is not, but then the
atmosphere also extends to over 60 miles) we can estimate the number of moles
of gas in it using the ideal gas equation, PV = nRT. The number turns out to be
1.7*1020 moles. Thus, CO2 introduced from burning a cmo
of oil corresponds to 2.7*1014/1.7*1020 or about 1.5 ppm
of the atmosphere.

Table. Volume of liquid CO2
produced from burning of 1 cmo of various fossil fuels and its concentration if it all ended up in
the air.

Fuel

Volume Liquid CO2 (mi3)

Conc. in Air (ppm)

Gas

1.9

1.0

Oil

3

1.5

Coal

4.3

2.1

The world is currently releasing about
36 billion tons of CO2 each year from combustion of coal, oil, and
natural gas, and that would correspond to about 4.5 ppm. The global CO2
level though is rising at the rate of about 2.5 ppm a year or about half the
value estimated. That is because about half of the emitted CO2 ends
up in the oceans and thus increasing their acidity. The increased acidity makes
it harder for corals, oysters, and plankton to develop their shells with potentially
dire consequences for the entire food chain!

An estimated
530 billion tons of carbon have been burnt since the start of the industrial
revolution. The expected rise in atomspheric CO2 concentration, if all of it
stayed in the air, would have been 245 ppm. The observed rise of 120 ppm
(current concentration of 400 ppm minus 280 ppm, the concentration in 1860)
jibes well with the assumed 50% staying in the air.

The greenhouse gas effect of the CO2 in air
amounts to increasing the radiative forcing by roughly 0.5 W/m2. That
seems like a small perturbation compared to solar insolation of 1000 W/m2
(at high noon). There is a nice video
describing how you can measure the solar insolation in your backyard with a
simple experiment. The net heat gained by the earth in a year can be estimated
by multiplying the surface area of the earth (41 1012 m2) by the radiative forcing (0.5 W/m2)
times the number of hours (8760) in a year, a factor that corrects for the fact
that only half
of the earth’s surface is facing the sun at a given moment, and that the sun is
not overhead all the time. The result is a net heat gain of 563 trillion kWh or
12.5 cmo! Since we are currently consuming 2.75 cmo of fossil fuels per year
that the additional heat being trapped from the greenhouse effect is
four-and-a-half times the energy released from burning of fossil fuels. There
goes the theory that the global warming is solely due to the heat rejected by
the engines.

Monday, April 20, 2015

Five years ago today the BP Deepwater
Horizon (DWH) oil well in the Gulf of Mexico burst into flames following a blow
out. Eleven workers died in the accident and 11 others were injured. Oil and
gas gushed out for months from the broken pipe at the floor of the sea. The
actual quantity of the spill was difficult to ascertain initially, and
estimates ranged from 10,000 to 100,000 barrels per day. After the fact, it was
determined that the maximum rate of spill was about 62,000 barrels a day and
over the three-month period of the spill, 4.9 million barrels of oil had poured
out. Even though this figure is questioned as it is important to the litigation
and fines that BP has to pay, the range of discrepancy has narrowed—somewhere between
3.2 and 4.2 billion barrels. Researchers are still trying to figure where
most of the oil went, because only about a quarter of amount has been accounted
for.

Over 600 miles of the coastline were
affected. Fishery and tourism are major industries of the region, and suffered
enormous losses. The damage to the environment, to the local flora and fauna,
and the destruction of their habitat was catastrophic in scope. There was a
marked decline in the population of shrimp, oysters, and various fish, and the
concern was that with the loss of much of their habitat, populations of
pelicans, turtles, and dolphins would also collapse. People feared that seafood
from the region would be contaminated with toxins threatening the industry. In
the immediate aftermath of the tragedy the headlines screamed of the
irrevocable damage to the fragile ecology of the area—that the place would forever turn into a wasteland.

Now, forever is a very long time. Not to minimize the catastrophe that
the DWH blowout was, it seemed to me though that the alarmist response was
uncalled for, and it distracted attention from the real restorative work that
needed to be done. Deepwater Horizon was only one of several major events in
which large amounts of oil were discharged into seas and oceans and these
accidents could provide some valuable lessons.

A year following the DWH blowout, I
wrote a post
about the accident. I looked at what happened after four specific incidents of
major oil spills:Amoco Cadiz, Ixtoc 1,
Exxon Valdez, and the sabotage by Iraqi army following the first Gulf War in
1991.I also noted that about 10 million
gallons of oil naturally seeps in the Gulf of Mexico every year. The main
conclusion I drew was that as tragic as these events have been for the people
and animals directly affected, they also provide a strong testament to the
resilience of the environment as recovery of the environment, and that we would
expect the Gulf of Mexico to also recover in three to five years.

I have been reviewing many of the
articles about the aftermath of the disaster. Some of the noteworthy findings
are:

·The
Food and Drug Administration tested
seafood from the Gulf of Mexico for contaminants but has found
few problems with toxicity.

·Studies on the
fate of the oil show that the oil-eating
microbes, which are endemic to the region because of the natural oil
seepage, feasted on the oil spill and biodegraded the oil. The sharp increase
in the population of these microbes could have reduced the dissolved oxygen and
adversely affect other species, but that scenario did not play out.

·Fish
and shrimp populations have rebounded to pre-disaster levels, and the seafood
industry has largely recovered. However, oyster harvests have not yet
recovered, possibly because of their limited mobility to move to oil-free
areas.

·Tourists
have returned to the region bringing with them the anticipated economic recovery.

To be sure there are still many
unanswered questions particularly about the long-term effects. The general
point I want to emphasize is that as with previous cases of oil spills, nature
has once again bounced back. It is not an excuse to be lackadaisical about oil
spills. Safety has to be number one on the minds when drilling for oil in the
seas, as it should be in many other industrial operations. Safe operating procedures
and disaster preparedness have to be constantly improved as new information
becomes available. At the same time we should recognize that oil is not an
acute toxin and oil spills do not spell the demise of the region. Nature is
remarkably resilient, and that’s worth celebrating.